Premiership Rugby, the umbrella body for English rugby's leading clubs, released details of the 'ground-breaking' deal earlier today that will see BT Vision become the exclusive broadcast partner for the Aviva Premiership from the start of the 2013-14 season.

In addition, the deal includes exclusive rights to any "matches played by Aviva Premiership Rugby clubs in any future European competitions from 2014-15 for three years" by which stage the current shareholder agreement governing the Heineken Cup and Amlin Challenge Cup will have expired.

However, European Rugby Cup Ltd (ERC), the organisers of both competitions, have since issued a statement insisting that any such deal "would be in breach both of IRB regulations and of a mandate from the ERC Board itself".

ERC also appeared to counter the deal struck by Premiership Rugby and BT with confirmation that they have agreed a four-year extension to their existing broadcasting deal with Sky Sports until the end of the 2017-18 season that clashes with the terms and the coverage detailed in the agreement between Premiership Rugby and BT.

ERC's deal with Sky Sports, that has been the exclusive UK broadcast partner for both European competitions for over a decade, covers: "Exclusive live matches from each of the first four rounds, plus all knock-out stages and finals for a further four seasons, across the UK and Ireland."

This would appear to conflict with the deal struck by Premiership Rugby and BT with question marks surrounding their ability to claim rights to away games played by English clubs while the release that accompanied their announcement made no mention of the knock-out stages or the final that would no doubt be played on a neutral ground.

ERC is adamant that Premiership Rugby has gone against a previous understanding. "European club rugby's six participant Unions have granted the authority to sell broadcast rights to its tournaments solely to ERC," the ERC statement added.

"It was unanimously agreed at an ERC Board meeting on 6 June, 2012 that ERC would conclude a new four-year agreement with Sky Sports for the UK and Ireland exclusive live broadcast rights to the Heineken Cup and the Amlin Challenge Cup until 2018. Premiership Rugby was party to that decision.

"ERC remains determined to honour its own commercial commitments and to continue its work to further develop the European club game."

The tit-for-tat exchange continued with Premiership Rugby rubbishing ERC's claims of misconduct. "Premiership Rugby notes the announcement by ERC concerning a broadcast deal with Sky Sports for the coverage of ERC competitions from 2014-15," it said in its most recent statement.

"ERC and its Board acknowledged and accepted that notice was served on the ERC Accord on 1 June 2012 by Premiership Rugby and Ligue Nationale de Rugby which means the Accord comes to an end in 2014. Sky Sports have been made fully aware of this.

"As a result of notice being served, ERC is not entitled after 2014 to sell the broadcast rights of matches involving Premiership Rugby clubs. On 27 July 2012 ERC was reminded of this in writing, and this was copied to Sky Sports.

"We also note ERC's reference to its Board Meeting on 6 June 2012. No specific broadcast deal was presented or voted on at this or any subsequent ERC Board meeting. In any case any such deal could not have included matches involving Premiership Rugby clubs.

"ERC's suggestion that Premiership Rugby may be in breach of IRB regulations is wrong. Following Premiership Rugby's agreement with the RFU, dated 16 October 2007 Premiership Rugby has specific consent to control the broadcast rights of its clubs.

"The deal which Premiership Rugby has completed with BT is financially strong for Premiership Rugby clubs and future European competitions bringing up to £152m into the game over the next four years. When any future European competition launches in 2014, BT will have exclusive rights to broadcast the matches played by Premiership Rugby clubs."

The public spat between two of the major stakeholders in the northern hemisphere is just the latest development in a simmering row over the future of the European club game with England's leading clubs seemingly intent on forcing a shake-up.

The current Shareholder Agreement between the leading sides from England, France, Ireland, Italy, Scotland and Wales, that governs the structure of the competitions, expires at the end of next season with the future of European rugby beyond that date currently being reviewed after Premiership Rugby and their French counterparts triggered a renegotiation period by serving notice to leave the competition.

The English and French clubs have threatened to go it alone if concerns about the qualification process, that they suggest favours RaboDirect PRO12 clubs, were not addressed, with proposals for a re-vamp already announced.

All ERC stakeholders are scheduled to convene in Dublin next Tuesday to begin the formulation of a new Shareholder Agreement for the 2014-15 season and beyond with Premiership Rugby chief executive Mark McCafferty quick to deflect any criticism of his organisation's bold step with the claim the BT deal will benefit the European game as a whole.

"We anticipate that this is the beginning of an excellent partnership with BT," he said in an earlier statement. "It's an outstanding deal to support the continued development of Premiership Rugby and in addition, the value of the European element from our clubs' rights will serve to help strengthen European rugby in its future competitions.

"Although the exact format of European competitions post 2014 is not yet agreed between the parties in Europe, this deal will certainly strengthen European club rugby for all parties.

"We are committed to finding an agreement including competitions which not only involve all teams from the existing European countries but also the emerging rugby markets. It is important that rugby continues to expand and grow. We have made proposals and we look forward to progressing discussions."